Lawyers representing the drug companies filed a motion Sept. 14 asking U.S. District Judge Dan Polster to recuse himself, claiming comments he made in and out of court showed he was biased toward wanting defendants to settle the case.

If drugmakers and distributors agreed to a settlement, they would have to spend money to fund addiction treatment and other aid for the affected communities.

In a written ruling, Mr. Polster said acknowledging the toll of the opioid epidemic does not make him biased, it makes him "human."

He also said it was impractical to expect another judge to be able to take over the lawsuit, which The Washington Post said could be the most complicated civil lawsuit in history, just weeks before it is set to begin.